The goal of this research is to provide a further understanding of interactions between the effectors and regulators of the immune response to herpes simplex virus (HSV) so that effective vaccines could be designed to control herpetic disease. The major emphasis of this phase of the research will be to explore the role of major histocompatibility complex restricted (MHC) class I and class II restricted cytotoxic T lymphocytes. Experiments are designed 1) to identify individual viral subcomponents that act as targets for class I and II restricted CTL in mice of various strains; 2) to define the optimal means of inducing CTL in vivo and in vitro and to find explanations for the apparent failure of some major glycoproteins to act as CTL targets and inducers; 3) to identify CTL recognizable epitopes on target proteins; 4) to further resolve the role of class I and class II restricted CTL of different specificities in controlling HSV pathogenesis; and, 5) to evaluate the role of suppressor mechanisms in regulating effector aspect of T cell mediated that serve to curtail infections.